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In this letter, we propose a novel approach for dynamically selecting an optimal relay mode and optimal transmission power levels in non-orthogonal multiple access wireless networks with relays. To maximize the network throughput, the proposed approach alternates between the one-relay mode and the two-relay mode based on channel state information. For the two-relay mode, we derive novel closed-form results on optimal power control. Unlike in a conventional one-hop network, it is not always optimal to allocate all power to the relay with the largest channel gain in the studied two-hop network. Based on the closed-form results, one could determine the optimal power levels quickly. Simulation results show that the proposed approach could significantly increase the network throughput.

The Pacific cupped oyster, Crassostrea gigas, is one of the major aquacultural shellfish species that has been introduced to Europe and America from its native source in the West Pacific. In Taiwan, the cultivated cupped oysters along the west coast have been identified as C. gigas for over centuries; however, several molecular phylogenetic studies have cast doubt upon the existence of this species in Taiwan and adjacent waters. Indeed, our analyses of mitochondrial cytochrome oxidase I (COI) sequences from 313 Crassostrea collected from 12 locations along Taiwanese and southern Chinese coastlines confirm that all samples were the Portuguese oyster, C. angulata, rather than C. gigas. Multiple lines of evidence, including haplotypic and nucleotide diversity of the COI gene, demographic history and population genetics, suggest that Taiwanese C. angulata is unique, probably experienced a sudden population expansion after the Last Glacial Maxima around 20,000 years ago and has a significantly limited genetic connectivity across the Taiwan Strait. Our study applies an extended sampling and DNA barcoding to confirm the absence of C. gigas in natural and cultivated populations in Taiwan and southern China, where we only found C. angulata. We highlight the importance of conserving the gene pool of the C. angulata population in Taiwan, particularly considering the current threats by large-scale environmental disturbances such as marine pollution, habitat destruction and climate change.

Background: Total anomalous pulmonary venous connection is a rare congenital heart disease that needs to be surgically corrected. In our study, we retrospectively evaluated the factors associated with mortality and morbidity in patients undergoing total anomalous pulmonary venous connection surgery. Patients and methods: Retrospective data were collected on 34 patients with isolated total anomalous pulmonary venous connection seen from 1990 to 2015. The median age at time of repair was 36 days (range, 1 to 2520 days) with median weight of 3.465 kg (range, 1.4 to 20.7 kg). Pulmonary venous obstruction, reintervention, associated factors for mortality and overall mortality were recorded and analyzed. Results: There were 16 deaths (13 surgical deaths and 3 late deaths due to pulmonary venous restenosis and reintervention). Preoperative pulmonary venous obstruction was presented in 21 patients (21/34, 61.8%) and was found to be associated with overall mortality (p=0.0052). Postoperative pulmonary venous restenosis was also a significant risk factor for mortality (p=0.0421). Emergent surgery is a risk factor for mortality (p=0.004). The associated risk factors, such as pre-operation ventilator FiO2, pre-operation inotropic use, postoperation ventilator FiO2 and post-operation epinephrine use were also associated with patient mortality. The initial SpO2 when arriving at our hospital was a protective factor for mortality. Conclusion: The overall mortality of total anomalous pulmonary venous connection patients has improved in recent years. However, preoperative pulmonary venous obstruction was still an important risk factor for mortality. Postoperative pulmonary venous restenosis was also a risk factor for mortality. Heart failure and emergent surgery were associated with higher mortality rates.

The complete mitogenome of the palemargin grouper, Epinephelus bontoides, was presented in this study. This mitochondrial genome consists of 16 903 bp, follow the typical gene arrangement with 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a non-coding control region (CR). The overall base composition was A, 28.7%; G, 16.1%; C, 28.0%; and T, 27.2%. The control region was 1200 bp in length, which located between tRNAPro and tRNAPhe, rich in A + T (69.2%) content. Based on the Neighbor-Joining (NJ) tree, E. bontoides was grouped with E. trimaculatus, E. quoyanus, E. areolatus, and E. bleekeri, and then combined with E. merra formed a clade. This complete mitogenome of E. bontoides can provide essential phylogenetic information of Epinephelus.

SUMMARY: New information on catch-at-age composition and length–weight relationships is presented for Pacific northern bluefin tuna caught by Taiwanese small-scale longliners in the southwestern North Pacific. The fork length – eviscerated weight relationship of Pacific northern bluefin tuna, Thunnus thynnus, caught off southwestern North Pacific (off the Taiwan coast) was determined and compared with relationships previously reported by various studies for different waters. The best representative of this relationship is W = 0.000023058L2.9342, where W is the eviscerated weight (kg) and L the fork length (cm). The eviscerated weights estimated from this relationship were multiplied by a scaling factor of 1.112 to obtain the estimated round weight. The visual comparison of weight-at-length showed that there were almost no differences between the relationships previously reported for the northwestern Pacific, the Sea of Japan and the present study. This indicated that Pacific northern bluefin tuna from those three waters could be of the same stock. Further assessment studies should combine information from those waters.

The complete mitogenome of the sixblotch hind, Cephalopholis sexmaculata was presented in this study. This mitochondrial genome consists of 16,589 bp, with 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a noncoding control region (CR), and its gene arrangement is identical to most vertebrates. The overall base composition of the heavy strand is A, 29.35%; G, 16.08%; C, 28.56%; and T, 26.01%. The COI gene started with GTG codon and the ATP6 gene started with CTG codon. The complete mitogenomic data may provide informative for further phylogenetic approach of species of Cephalopholis and related genera belong to the Epinephelidae groupers.

The effects of 2,3-butanedione monoxime (BDM) on induction of action potential bursts were studied pharmacologically on the RP4 central neuron of giant African snail (Achatina fulica Ferussac). The effect of okadaic acid on the neuron was also tested. The RP4 neuron showed a spontaneous firing of action potential. Okadaic acid (1 µmol/l) did not alter the frequency of spontaneous action potential while BDM (3 mmol/l) reversibly elicited bursts of potential (BoP) of the RP4 neuron. The BoP elicited by BDM (3 mmol/l) were reversed 20 min after incubation with diazoxide (500 µmol/l) while the BoP were not altered in preparations treated with okadaic acid and BDM. The BDM-elicited BoP were not inhibited after administration with (a) hexamethonium (100 µmol/l), (b) atropine (1 mmol/l), (c) d-tubocurarine (100 µmol/l), (d) prazosin (100 µmol/l), (e) propranolol (100 µmol/l), (f) calcium-free solution, (g) high K+ (12 mmol/l) or (h) with high Mg2+ (30 mmol/l) solutions. The BDM-elicited BoP were inhibited by pretreatment with KT-5720 (10 µmol/l) or H89 (10 µmol/l), the protein kinase A inhibitors. However, the BoP were not affected after application of chelerythrine (10 µmol/l) or Ro 31-8220 (10 µmol/l), the protein kinase C inhibitors. Voltage-clamped studies revealed that BDM elicited a negative slope resistance (NSR) at membrane potentials between –50 and –10 mV. The NSR was not detectable at the same membrane potential in control RP4 neuron. It is suggested that the BoP elicited by BDM were not due to (1) the synaptic effects of neurotransmitters; (2) the activation of cholinergic, adrenergic receptors, or (3) phosphatase activity of the neuron. The BDM-elicited BoP were dependent on the protein kinase A related cAMP in the neuron and the delayed outward K+ current may contribute to the BDM-elicited BoP.